The present invention broadly relates to a new and improved method and apparatus for opening printed products which have been folded off-center.
Generally speaking, the present invention relates to a new and improved method for opening printed products which have been folded off-center or asymmetrically. One portion of such printed products, namely the open or fan edge opposite to the folded or spine edge, possesses a leading edge or marginal lap section. That is to say, one lap or edge of this open or fan edge protrudes or projects marginally beyond the other lap or edge. The printed products are gripped at their folded edge and conveyed in a direction which is transverse to the folded edge. One portion of the printed products is temporarily gripped in the region of the aforesaid open edge during product conveyance for separating or opening both portions of the printed products.
In other words, the method of the present invention is for opening asymmetrically or off-center folded printed products and comprises the steps of holding each printed product of the asymmetrically folded printed products at a folded edge thereof, each printed product possessing a leading marginal lap on an open edge thereof which is located opposite the folded edge.
The present invention also relates to a new and improved construction of an apparatus for opening printed products which have been folded off-center or asymmetrically. One portion of these printed products, namely the open or fan edge opposite to the folded or spine edge, possesses a leading edge or marginal lap section. That is to say one lap or edge of this open side edge protrudes or projects marginally beyond the other lap or edge. A conveyor is provided having clamps or grippers which are mutually separated or spaced by a predetermined distance or spacing and which are provided for holding the printed products at their folded edge. A product opening or spreading device or apparatus is furthermore provided and is located below the conveyor. This opening device or apparatus possesses circulatingly or revolvingly driven, controllable gripping elements or grippers for temporarily gripping one of the portions of the conveyed printed products in the region of the aforesaid open edge.
In other words, the apparatus of the present invention is for opening asymmetrically folded printed products and comprises at least one feeder or feeder device. The asymmetrically folded printed products each possess a leading marginal lap on an open edge thereof which is located opposite a folded edge thereof.
Furthermore, the present invention also relates to a new and improved construction of an installation for collating printed products which have been folded off-center or asymmetrically and comprising a plurality of the aforesaid opening or spreading devices or apparatuses positioned or located substantially in succession in the product direction of conveyance of the collating apparatus.
In other words, the collating installation of the present invention is for collating asymmetrically or off-center folded printed products and possesses at least two opening apparatuses or devices arranged in succession in a predetermined direction of conveyance of the printed products.
An example of a prior art apparatus of this type is disclosed in the European Patent Application No. 0,095,603, published Dec. 7, 1983, which is cognate to the U.S. Pat. No. 4,489,930, granted Dec. 25, 1984. In this prior art apparatus, the printed products which have been folded off-center and which are to be opened are conveyed such that their folded edges precede or lead and take on a backwardly falling slanted or oblique position. The printed products are grasped at their folded edges by means of grippers of a conveyor. These grippers project backwardly with respect to the direction of conveyance. An opening or spreading device positioned below the conveyor is equipped with circulatingly driven, controllable clamps or grippers. These clamps serve for temporarily holding the leading edge section (termed marginal lap) on the uppermost portion of the advancing printed products. An acceleration belt or strap is positioned subsequent to the circulation track for the clamps. This acceleration belt is circulatingly driven at a higher speed than the clamps. As soon as the lowermost portion of the printed products, which is not held by means of the clamps, is displaced or conveyed into the effective region of this acceleration belt, this lowermost portion of the printed product is entrained as a result of the frictional contact made with the acceleration belt and is separated from the uppermost portion, which is held by means of the clamp. The printed products which are opened in this manner are then dropped or released onto circulating support bars or arms of the collating apparatus upon which the printed products come to rest in a straddled position.
This known prior art solution is expensive or laborious to construct since an acceleration belt or strap is necessary in addition to the circulation track for the clamps. The separation of the product halves, i.e. the opening of the printed products, depends on the frictional entrainment of a portion or section of a printed product by means of the acceleration belt. A reliable or positive opening of the printed product is not ensured under all conditions, especially not if both portions or sections of the printed product adhere to one another in a manner which is more tenacious than usual.